We study the shear flow of two-dimensional foams, i.e., a monolayer of bubbles floating on a soapy solution. We successfully connect local and global flow behaviour
The effect of spin-orbit coupling on various quantum transport phenomena is considered. The main topics discussed are: * How spin-orbit coupling can induce shot noise through trajectory splitting. ... Show moreThe effect of spin-orbit coupling on various quantum transport phenomena is considered. The main topics discussed are: * How spin-orbit coupling can induce shot noise through trajectory splitting. * How spin-orbit coupling can degrade electron-hole entanglement (created by a tunnel barrier) by mode mixing. * Mesoscopic Spin Hall effect: longitudinal charge current leads to transverse spin currents in a chaotic electron cavity which has universal fluctuations around a zero mean. * How smooth disorder increases the conductivity of a graphene sheet. In addition a detailed introduction is given to both the origin of spin-orbit coupling and the consequences of time reversal symmetry in quantum systems. Show less
A low-temperature scanning tunneling microscope is used to perform spin-excitations on individual magnetic transition metal atoms when placed onto a crystal surface. By following these excitations... Show moreA low-temperature scanning tunneling microscope is used to perform spin-excitations on individual magnetic transition metal atoms when placed onto a crystal surface. By following these excitations while applying external magnetic fields the precise influence of the anisotropic crystal field on the spins of iron and manganese atoms is investigated. Similar experiments on an individual cobalt atom lead to the observation of a Kondo resonance. This can be explained by showing that the crystal field reduces the 3/2 spin state to an effective spin-1/2 Kramers doublet. The influence of the local environment (i.e. magnetic field, crystal field anisotropy and spin-coupling to neighboring atoms) on the characteristics of the Kondo resonance is studied. Show less
A surface plasmon is a purely two-dimensional electromagnetic excitation bound to the interface between metal and dielectric and quickly decaying away from it. A surface plasmon is able to... Show moreA surface plasmon is a purely two-dimensional electromagnetic excitation bound to the interface between metal and dielectric and quickly decaying away from it. A surface plasmon is able to concentrate light on sub-wavelength scales __ a feature that is attractive for nano-photonics and integrated optics. Light couples to a surface plasmon via surface roughness or an irregularity and vice versa. Most experimental and theoretical work on surface plasmons is concerned with metallic structures that contain one or two-dimensional arrays of close-lying sub-wavelength holes or slits. In this thesis a much simpler system of only a few parallel sub-wavelength-wide slits is used as a playground for surface-plasmon studies. Amplitude and phase characteristics of the light-plasmon-slit interaction events, like coupling, reflection and plasmon hopping over a slit, are studied via corresponding interference phenomena. Moreover, a single subwavelength-wide slit displays a wave-plate behavior, as a result of a finite conductivity of the metal film. Show less
